The use of solidification technology and solid block detergents in institutional and industrial operations was pioneered in the SOLID POWER.RTM. brand technology claimed in Fernholz et al., U.S. Reissue Pat. Nos. 32,762 and 32,818. Additionally, sodium carbonate hydrate cast solid products using substantially hydrated sodium carbonate materials was disclosed in Heile et al., U.S. Pat. Nos. 4,595,520 and 4,680,134. In recent years attention has been directed to producing highly effective detergent materials from less caustic materials such as soda ash also known as sodium carbonate. Early work in developing the sodium carbonate based detergents found that sodium carbonate hydrate based materials swelled, (i.e., were dimensionally unstable after solidification). Such swelling can interfere with packaging, dispensing and use. The dimensional instability of the solid materials relates to the unstable nature of various hydrate forms prepared in manufacturing the sodium carbonate solid materials. Early products made from hydrated sodium carbonate typically comprised a one mole hydrate, a seven mole hydrate, a ten mole hydrate or more typically mixtures thereof. After manufacture, upon storage at ambient temperatures, the hydration state of the initial product was found to change. Often this change involved a change from a dense hydrate to a less dense hydrate and resulting in an increase in volume of the block product. This hydrate change was believed to be the cause of the dimensional instability of the block chemicals. Substantial efforts were made to forming a solid comprising a one mole hydrate that was chemically and dimensionally stable. Substantial success was achieved in this research and development project. However, further work was directed to both the chemistry and processes involved in cast solid block manufacture. Detailed experimentation was directed to different compositions that could be used in manufacturing sodium carbonate detergents. Further, significant process studies were initiated to develop improved process parameters in manufacturing solid block detergents.
A variety of investigative programs were initiated to explore the parameters of solid block detergent manufacturing using casting and extrusion technology. The economics, processability, utility and product stability of the solid products were continually investigated to obtain improvements over quality and useful products.